but I don't see people dressed up for dinner hardly anywhere any more. I totally get the "I'm on vacation" attitude, and that it's time consuming to change clothes.
1) IMHO, when people dress so casually, they behave differently in/at the restaurant.
2) To me, it seems, when people dress better, they behave better.
3) Yes, I admit this is personal opinion.
Nope, Park attire for me no matter where Im eating, which all complies with the rules. Unless we choose to do V&A that will not change in the foreseeable future.
Interesting.... We take as little luggage as possible yet still manage to take a few smarter outfits each. For the three of us we only have two suitcases for two weeks vacation that are always underweight. I totally get what you mean about not wanting to wear business attire if you have to wear it all year around.Let me start by saying we generally dress up slightly for signature dining (boys in dress shorts and a polo and DH in similar fashion. I might wear dress shorts and a short sleeveless blouse (depending on the time of year). Part of the Disney "draw" for our family is that DH who has to travel weekly and wear business clothes daily LOVES that he can have fine dining in Disney while wearing something that feels like "vacation" clothing, not work-wear! Another factor for us in not completely dressing up is luggage. Depending on how many of us are traveling and which airline we are flying we can be paying for 4-12 (sometimes our six sons and soon to be four wives travel with us) checked bags each way. If we take a small carry on full of shorts, tees (maybe a polo or blouse thrown in) we can save a bundle on baggage fees.

We dress for dinner when in WDW. That said we allow plenty of time to return to our room, shower and change and take transport to the restaurants. Good quality polo shirts or short sleeved shirts for the guys and Suitable footwear and for me usually a nice dress that's comfortable but smart and a pair of strapped sandals.
We have been a little disappointed to see folks at Signature restaurants in swimwear and flip flops dining next to families who have taken notice of the dress code required and stated when booked. Honestly they need to tighten up on the dress codes. I can appreciate folks can get waylaid during the day by other events and kids get tired ( heck even the adults do too ). BUT Why insist on booking the ADRs that the restaurant has a dress code if they just ignore it when it suits them to?